In recent years, much attention has been given to a CAI (Computer-Aided Instruction) system which can provide, in an interactive manner, instructions corresponding to individual learning levels, as well as multitudinous instructions, using a computer. In the basic CAI system, a plurality of learning terminals provided in a classroom are connected to a host computer. Instructions corresponding to individual learning levels are provided such that the entire progress of a class is managed using the computer, while problems are posed to the respective terminals and answers are received therefrom, in an interactive manner. In this CAI system, a key-operation console for specifying which of the learning terminals is/are to be used is provided at a teacher's side, so that various instructions and information are supplied from the teacher to students utilizing the learning terminals, via the key-operation console, or a teacher can selectively communicate with the students.
The conventional CAI system described above is designed in accordance with the layout of a classroom, and a special-purpose key-operation console is designed and manufactured in accordance with the arrangement of learning terminals in the classroom. However, there are various classroom layouts; for example, 20 students (4 rows.times.5 columns), 24 students (4 rows.times.6 columns), 48 students (6 rows.times.8 columns), 40 students (8 rows.times.5 columns). Therefore, if the key-operation console is designed and manufactured in accordance with a specific classroom layout this results in high equipment cost. In addition, if key-operation consoles corresponding to specific classroom layouts are individually manufactured, this results in poor maintainability.
It is proposed to combine a predetermined number of keys to constitute a module key, and to combine a plurality of such module keys to arrange, at low cost, a key-operation console corresponding to the desired classroom layout. However, as is shown in FIG. 1, when key modules, each consisting of five keys, are used to realize a key-operation console for a classroom where 24 learning terminals T1 to T24 are arranged in a 6 (rows).times.4 (columns) matrix, this presents the following drawback:
In this case, since the necessary number of keys is 24, five key modules are prepared. Five key modules KM1 to KM5 are arranged, to realize a key-operation console, as is shown in FIG. 2. For this reason, the key matrix differs from the learning terminal matrix in the classroom. As a result, the correspondence between the keys and the learning terminals is rendered unclear, thus resulting in poor operability of the key-operation console.